Bad news for national park lovers: a new study published in Science Advances has found that many national parks have levels of of air pollution on par with major US cities. In parks such as Sequoia, Acadia, and Joshua tree, toxic ozone levels breaching the safe limit set by the EPA rivaled those found in cities such as New York and Los Angeles, which has the worst air quality rating of cities in the United States. While the number of dangerous pollution days has fallen for both cities and parks since the 1990 enactment of the Clean Air Act and the EPA’s Regional Haze Rule of 1999, experts are pressing for more regulation after this week’s findings.

National parks see an 8% decline in visitor numbers, on average, in months recording two to three days of bad air quality. The statistics suggest that many of the parks’ guests choose to come not only for the sights, but for their health as well. And, while some have criticized Regional Haze Rule regulations, study co-author Ivan Rudik disagrees. An assistant professor at Cornell University, Rudik stated that “some of the arguments that people are making against the Regional Haze Rule are that the benefits are basically zero, that these visibility rules don’t matter much or maybe the health improvements are overstated. But if you look at what people actually do, they clearly do care.”

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Recent years have seen record-breaking numbers of visitors to national parks, yet another reason to reevaluate government standards when it comes to air pollution. Speaking to The Associated Press, Rudik remarked that “even though the national parks are supposed to be icons of a pristine landscape, quite a lot of people are being exposed to ozone levels that could be detrimental to their health.”

+ Science Advances

Via Ecowatch

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